Published: 08 Feb 2004
Proponents of information life cycle management (ILM) like to talk about managing data from birth to death. For most industries, that "death" can't come soon enough. But for others--genealogists, historians, scientists--the challenge is to keep data around for as long as possible. And as more and more digital documents accumulate, the chore of sorting out the various ways to preserve them for the long term is falling to IT departments.
Even if you don't need to archive data for very long--say seven or 10 years, as is often the case in financial services--you still have a lot of work ahead of you, explains Paul Greene, director of the storage division of Digital Storage Solutions, a document management provider in Brentwood, NY.
Your first task is to select an appropriate archive medium and file format. For most archive applications, Greene recommends professional-grade optical disk, such as Plasmon's new UDO drive. Compared to bare media optical disks such as CD and DVD, UDO's protective casing does a good job of protecting the media from damaging dust particles and scratches.
Tape, meanwhile, is probably not a good choice, Greene says. Issues inherent to the media--such as the fact that it needs to be periodically spun and that the heads touch the physical media--make it vulnerable to wear and tear. "It's disheartening to see tape manufacturers sell tape where it doesn't belong," he says. "Yet it happens all the time."
But even if you select media that can survive for the next 100 years, you'll still need to archive the servers, drives and applications used to create the data if you want to retrieve it. A more likely scenario is that you'll have to migrate your data every, say, five years, to newer, supported media. Greene's own customers do this regularly, he reports, performing data migrations away from say, 12-inch optical disks to UDO, or from CD to DVD.
Indeed, the media's shelf life is only part of the problem. More often than not, when it comes to long-term archive, "the media outlives the technology used to access it," says Steve McCown, a development engineer for StorageTek's advanced technology group. Together with StorageTek fellow Michael Leonhardt, the two have developed a proof-of-concept technology called the Century Archive Project that if ever commercially developed, might make it possible to skip the media migration step.
The idea behind the Century Archive Project is simple enough: On the same magnetic media, store a document in both its digital and analog form. For as long as the media is viable, you can access the document digitally. But once the media starts to deteriorate, you can magnify the analog view of the document, potentially scanning it to return it to a digital format. Based on optical tape drive technology, the process can store color by separating out the reds, greens and blues.
For those interested in truly long-term archive, there's the feeling that analog technology still has an important role to play. Indeed, the microfilm industry is still alive and well, and there are even startups developing longer-life alternatives to it.
One such startup is Norsam Technologies in Hillsboro, OR, which has developed a technology that records images on non-corrosive metal, for the ultimate in survivability. Norsam's HD-Rosetta is a 4x6-inch metal plate onto which you etch compressed analog images using an ion beam laser. It will be introduced at next month's Association for Information and Image Management in New York City, as a competitor to traditional microfilm.
There are even ways to preserve inherently digital data in analog fashion. For example, database archive software maker OuterBay last fall introduced a new product called Encapsulated Archive, which stores database records in self-describing, human-readable XML format.
"This is a final form technology," says Michael Howard, OuterBay CEO, "independent of storage, media and application." Granted, "it's a bit verbose, bombastic" he says, but like a politician, "it wants to make itself understood to the masses."
For others, the idea of trying to store data as analog documents is misguided. "Look at the texts that survive from antiquity," says Dr. Richard Bradshaw, an IBM distinguished engineer. Many survived only because multiple copies were stored at different locations, say, at the at the Library of Alexandria and in European monasteries. In the same vein, if we want to preserve data for future generations, Dr. Bradshaw says, we should "make it as easy as possible to make copies of the data all over the world."